Diesel fuel supplies can become contaminated with water which can, in turn, contaminate the fuel supply for a diesel engine of a motor vehicle. To counter this problem, it is common to provide a diesel filter to separate water from the fuel supplied to the engine. This is known as de-watering.
The diesel filter typically has a water trap in which water collects over a period of time. A water-in-fuel (WIF) sensor detects when the amount of water collected in the water trap has reached a predefined threshold. A notification, such as a lamp on the dashboard, indicates that the collected water should be drained from the diesel filter. The drainage is performed by opening a drainage valve provided on the diesel filter. This is not a specialist operation and it is intended that an individual can drain the water from the diesel filter without specialist knowledge or tools.
The drainage valve is typically provided at the bottom of the diesel filter and is opened and closed by rotating a thumbwheel provided at the base of the diesel filter. The thumbwheel typically has a knurled or ridged outer edge to allow it to be gripped by an individual. However, if there is limited or restricted access to the diesel filter, the individual may not be able readily to grip the thumbwheel; this may render it more difficult to operate the drainage valve. As fuel will also drain through the diesel filter, this can prove particularly problematic if the individual cannot readily close the drainage valve once the trapped water has been drained. Moreover, the thumbwheel may be contaminated with fuel rendering it more difficult to grip.
The present invention sets out, at least in certain embodiments, to overcome or ameliorate at least some of the above problems.